possible NPE in BridgeSnapshotReader

Just noticed this in BridgeSnapshotReader:

code

                String firstLine = null;
                while ((firstLine = br3.readLine()) != null) {
                  if (firstLine.startsWith("@")) {
                    continue;
                  } else {
                    break;
                  }
                }
                if (firstLine.startsWith("published ")   // possible NPE?
                    || firstLine.startsWith("flag-thresholds ")
                    || firstLine.startsWith("r ")) {
                  bdp.parse(allData, dateTime, authorityFingerprint);
                  parsedStatuses++;